Since we're dealing with radial acceleration around a circle, I used the radial acceleration equation a=v²/r. At the top of the hill, the force upward exerted by the hill is less than the weight of the sled. if v is large enough the term (g-v²/r) will become 0 and the sled will fly off the ground as it reaches the peak. Let me know if I can clarify any of my work.
The radius of the sphere is r=5.15 cm=0.0515 m, and its surface is given by

So the total charge on the surface of the sphere is, using the charge density

:

The electrostatic force between the sphere and the point charge is:

where
ke is the Coulomb's constant
Q is the charge on the sphere

is the point charge
r is their separation
Re-arranging the equation, we can find the separation between the sphere and the point charge:
Answer:
The answer to your question is: F = 924 N
Explanation:
Data
v = 28 m/s
m = 66 kg
d = 56 cm
F = ?
Formula
v = d/t
a = v/t
F = ma
Process
t = d/v = 56 / 28 = 2 s
a = v/t = 28 / 2 = 14 m/s²
F = 66 (14) = 924 N
Answer:
no it would not. that is an open circuit and it would need to be closed at the switch for current to flow.